Type-writing machine.



H. V. FENGLER.

TYPE WRITING MACHINE.

APPLICATION nuzo JULY 31,1914.

1,2 1 9,540. Patented Mar. 20, 1917.

' Fig.1.

I |NVENTOR= BY @Mf ATTORN Y WITN ESSES- HERMANN' v. FEivGLER, or

UNDERWOOD TYPEWRITER COMPANY, OF NEW YORK, N.

DELAWARE.

Specification of Letters Patent.

WEST PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO ,Y., A CORPORATION OF TYPE-WRITING MACHINE.

Patented Mar. 20, 1917.,

Application filed July 31, 1914. Serial No. 854,236.

To all whom it may concern:

Be it known that I, HERMANN V. FENGLER, a citizen of the United States, residing in Vest Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain newand useful Improvements in Type-\Vriting Machines, of which the following is a specification.

This invention relates to typewriting ma chines adapted for making entries on a series of bills or other work-pieces which are placed on the machine serz'atz'm, a tally sheet or other record sheet being retained on the machine to receive the record copies of the entries on a number of bills.

More particularly, the invention relates to means for rotating the platen forwardly a predetermined distance to position a bill I on the platen for being written upon, and,

after the typewritten entries have been made, for rotating the platen backwardly to permit the removal of the completed bill and position the platen and record sheet for the introduction of a succeeding bill, the forward rotation of the platen being through a somewhat greater angle than the backward rotation, whereby the removal of one bill and introduction of the succeeding bill automatically advances the record sheet a predetermined distance to provide suitable spacing between the record copies of the entries on the several bills.

The invention embodies a novel construction for carrying out the same general'purpose as that set forth in my copending applications Nos. 8%,933 and $6,934.

in the present invention, the driver for rotating the platen backwardly and forwardly for removing a bill and for positioning a succeeding bill on the platen, may be in the form'of a disk or rotary driver, freely mounted on the platen "axle and adapted to be locked to the platen by means of a coupler carried by the driving disk, and which coupler may be in the form of a coupling pin projectable into any one of an annular series of openings in the line-space ratchet wheel or other part rotating with the platen. The coupling pin may extend transversely through the driving disk and be locked to the line-space wheel by a sta tionary disk or holding plate on the opposite side of the driver from the line-space wheel, said holding plate formed with a recess in position to permit the coupling pin to be withdrawn by a spring from the line-space wheel when the driver has reached the limitof its rotation in a direction to advance the work-piece on the platen, such limit being determined by a stop. Further rotation of the platen independently of the driver is thus permitted while entries are being made on the work-sheet.

After the entries on a bill have been completed, the driving disk 1s rotated in the reverse direction to rotate the platen backwardly, said recess in the holding plate permitting a limited rotation of the disk before the coupling pin is projected to engage the line-space wheel; so that the backward rotation of the platen is through a shorter distance than the forward rotation by the driving disk, thus providing suitable spaces on the record sheet between succeeding entries. A stop adjustable along a graduated scale on the driver determines the amplitude of oscillation of the driver and may be set to correspond to the depth of the top margins or pivoted headings of the work-pieces.

Other objects and advantages will hereinafter appear.

In the accompanying drawing, Figure 1 is a part sectional perspective view showing the invention applied to an Underwood typewriting machine.

Fig. 2 is a detail sectional view showing the coupling pin connecting the driver to the line-space wheel.

Fig. 3 is a sectional plan view of the invention.

Fig. i is a part sectional end elevation view, the driving disk being at the forward limit of its movement.

Fig. 5 is a similar view showing the driving disk at the limit of its backward movement. 7

Fig. 6 is a view similar to Fig. 2, but with the coupling pin'retracted to disconnect the driver from theplaten.

Fig. 7 is a part sectional end elevation view showing the work-pieces in position to be written upon.

Fig. 8 is an enlarged perspective view partly broken away, showing the driving disk and associated parts.

The roller platen 1 is fixed to an axle 2 journaled in the ends 3 of a platen frame which may also comprise an inclined paper space intervals.

shelf 4 located at the rear or intake side of the platen, said shelf connecting the platen ends 3. Type-bars 5 (Fig. 7 may be operated in the usual manner to'strike against the work-sheets at the front face of the platen. The platen may be rotated either by a hand wheel 6 fixed to the platen axle, or bya line-space mechanism comprising a line-space ratchet wheel 7 secured to the platen axle, said ratchet wheel rotated by a pawl 8 pivoted to a sliding bar 9, the latter actuated by a line-space lever 10.- having an arm 11 to engage the front end of the slide 9 and move it rearwardly to cause the pawl to rotate the line-space wheel and the platen. The line-space wheel may be held against accidental rotation by a detent 12 held by a spring 13 against the line-space wheel.

The driver for rotating the platen forwardly and backwardly for placing'a bill in position to be written upon and then returning it to position to be removed from the machine, is herein shown'as a disk or wheel 11 freely mounted on the platen axle 2, adjacent to the line-space wheel 7. The driver is releasably connected to the platen by a connector in the form of a coupling pin 15, extending transversely through the disk '11 and adapted to have its inner end projected into any one of an annular series of openings 16 in the line-space wheel 7. The openings 16 are preferably spaced at the same angular distances as the ratchet teeth on the Wheel 7, so that the connecting points of the driver with the platen are at line- While the platen is 'being rotated by the driver 11, the pressure of the driver and line-space wheel against the locking bolt or latch 15 in a direction transversely thereof is sufficient to hold said bolt in locking position. A stationary holding plate or disk 17 which lies against the outer face of the driver, provides a positive means to prevent the locking bolt from moving to unlocking position. The driver may be recessed to receive the plate 17 so that said plate is flush with the driver as shown.

During the rotation of the driver,- the outer end of the coupling pin 15 bears against the inner face of the plate 17 and is thus positively held in coupling position. The plate'17-may fit loosely on the platen axle and is rigidly held stationary with the platen frame by means of a bracket 18, -fixed at its ends to the platen frame and said plate respectively, said bracket being off-set -to extend around the driver 14. The rotation of the driver to rotate the platen forwardly, that is, in line-feeding direction, is limited by a stop 19 fixed thereon, intercepted by the bracket 18. The rotation of the driver in the reverse direction is limited by an ad justable stop 20, also intercepted by the bracket 18. .The stop 20 is adjustable along an annular slot or groove 21 in the periphery of the disk 14, said groove formed with lateral recesses 22 to accommodate a nut 23 threaded on the stop 20, so that by rotating the stop pin 20, it may be loosened, then moved along the periphery of the disk to any position of adjustment, and then clamped in such position.

A graduated scale 2% on theperiphery of the driver indicates the position to which the stop 20 has been adjusted, relatively to the stop 19, the scale graduations preferably representing line-space intervals and being numbered to indicate the number of line-spaces through which", the platen may be rotated by the driver for any adjustment of the stop 20.

For practical purposes of construction and assemblage of parts, the driving disk 11 may comprise a ring 25 made separate from the body of the disk but rigidly secured thereto in the assembled machine.

The work-pieces may comprise a tally sheet or other record sheet 26 to receive the record copies of typewritten entries on a series of printed forms, bills, or other workpieces 27, a carbon sheet 28 being placed between the original and record sheets 27 and 26. In Fig. 5, the driver is shown at the limit of its rotation in a direction to rotate the platen backwardly, the stop 20 being against the bracket 18, and the connector 15 locked to the line-space wheel. The bill that has been completed having been removed from the machine, a succeed- 1 as shown in Fig. 5, with its leading edge against the rear pressure roll 29. The driver 11 is now rotated to the Fig. 7 position in which the stop 19 is against the bracket 18, thus rotating the platen forwardly and bringing the work-sheet 27 into position to be written upon.

During this forward rotation of the platen, the coupler 15 is positively held locked to the line-space wheel by the plate 17 until the coupler reaches a recess 30 in said plate, and during the continued rotation of the driver, said coupler is frictionally held in locking position until the pin 19 strikes the bracket 18, when a coil spring 31, between a shoulder 32 on the pin-15 and .a nut'33 threaded in the disk 14, snaps said pin into the Fig. 6 position, thereby releasing the platen and permitting it to be rotated independently of the driver as typewritten entries are made on the work-sheet.

After the entries on the work-sheet have been completed, the driver 14 is rotated to the Fig. 5 position. During the initial portion of this rotation the coupling pin 15 moves along the slot 30 so that the platen is not rotated until the cam end of the slot forces the coupling pin into engagement with the line-space wheel, after which the ing bill 27 is placed in position on the shelf platen is positively rotated backwardly with the-driver to the Fig'. 5 position.

It will thus be seen that the backward rotation of the platen by the driver is through a less distance than the forward rotation, by an amount determined by the length of the slot 30 which, as shown, corresponds to two line-space intervals. As a result, the record sheet 26, when a new bill is being brought to writing position on the platen, is always fed forwardly through a distance of two line-spaces'more than it is moved backwardly in removing the preceding bill, so that the record entries for the several bills are suitably spaced. It will be understood that the slot 30 may be of any length desired.

The stop 20 forms a gage determining the position to which each bill will be brought for receiving the first line of writing, and is adjustable to accommodate bills having top margins or headings of different depths.

As shown in Fig. 4, the record sheet 26 is advanced to a position assumed after number of entries have been made thereon. The feed rolls 29 and 29 (Fig. 4:) may be lifted from the platen by means of a keyoperated cam shaft 34, as is common in the Underwood machine, said shaft operable, when rotated, to swing the levers 35 about their pivot 36, and thus remove the feed rolls carried by said lever away from the platen;

Variations may be resorted to within the scope of the invention, and portionsof the improvements may be used without others.

Having thus described my invention, I

- claim 1. In a typewriting machine, the combination with a revoluble platen, of a driver for rotating the platen backwardly a predetermined fixed distance for carrying a work-.

' piece into position to be removed from the machine, and replaced by anew work-piece, and then rotating the platen forwardly a greater distance than said backward rotation to position the new work-piece on the platen, a stop to determine the limit of movement of the driver when rotating the platen forwardly, a coupler carried by the driver and movable thereon intoand out of position for connecting the driver to the platen, means to automatically actuate the coupler to connect the driver with the platen when the driver is in an intermediate position during its rotation in the direction to rotate the platen backwardly and thereafter cause the driver torotate the platen backwardly,'a stop to limit the rotation of the driver in said direction, said coupler being frictionally held in coupling position by the and .means'to' automatically retract the cou- ""p'leF to -u-ncoupling positiorr when the fortion with a platen, of an oscillating driver for rotating the platen forwardly a predetermined distance and rotating the platen backwardly a less distance, a coupler carried by the driver and movable thereon into and out of coupling position to form a driving connection between the driver and platen during said rotations, means to operate the coupler to release the driver when the latter reaches the limit of its rotation in a direction to rotate the platen forwardly, the coupler being held in coupling position during the final portion of said forward rotation by the pressure applied thereto by the driver in rotating the platen, and means to operate the coupler -to connect the driver with the platen when the driver is at an intermediate point during its rotation in the reverse direction.

3. In a typewriting machine, the combination with a platen,0f an oscillating driver for rotating the platen forwardly a predetermined distance and rotating the platen backwardly aless distance, a coupler carried by the driver and movable thereon into and out of coupling position to form a driving connection between the driver and platen during said rotations, means to "operate the coupler to release the driver when the latter reaches the limit of its movement in a direction to rotate the platen forwardly, the coupler being held in coupling position during the final portion of said movement by the pressure applied thereto by the driver in rotating the platen, means to operate the coupler to connect the driver with the platen when the driver is at an intermediate point during its-movement in the reverse direc-- tion, and stops to limit the throw of the driver in both directions, one of said stops adjustable to vary the throw of ,the driver, and thereby vary the angle through which the platen is rotated by said driver.

In a typewriting machine, the combination with a platen, of a driver, a coupler carried by the driver and movable thereon into and out of coupling position for connecting the driver to the platen to rotate the latter as the driver is rotated, the driver in rotating the platen applying to the coupler to actuate said coupler and disconnect the platen from the driver when the latter has completed said movement, thereby permitting the platen to be rotated independently of the driver, means to operate said coupler when "the driver is rotated in the reverse direction, and thereby connect the driver carried by the driver and movable thereon into and out of coupling position for conneeting the driver to the platen to rotate the latter as the driver is rotated, the driver in rotating the platen applying to the coupler a pressure operative to prevent movement of the coupler to uncoupling position, a stop to limit the movement of the driver in a directiqn to'rotate the platen forwardly, means to actuate said coupler and disconnect the platen from the driver when the latter has completed said movement, thereby pern'iitting the platen to be rotated independently of the driver, means to operate said coupler when the. driver is rotated in the reverse direction, and thereby connect the driver with the platen, said means permitting a limited rotation of the driver relatively to the platen in said reverse direction, whereby the platen is rotated backwardly a less distance than forwardly by the driver, an adjustable stop limiting the rotation of the driver in rotating the platen baekwardly and cooperating with the first-mentioned stop to determine the extent the platen may be rotated forwardly by the driver, and a graduated scale cooperati'ng with said adj ustable stop to indicate the distance through which the platen may be rotated forwardly by the driver. v

G. The combination with a rotary platen, of an oscillating driver, stops to limit the movement of the driver in both directions, a coupler connecting said driver with the platen, means to automatically operate said coupler to release the driver from the platen when the driver completes its platen-ad vaneing movement, and permit the-platen to rotate independently of the driver, said driver having a limited movement in the reverse direction independently of the platen, and means to actuate said coupler to connect the driver with the platen and rotate the platen with the driver during the remainder of the movement of the driver in said reverse direction, said coupler held in driving relation to the platen during the final portion of said platen-advancing movement by the pressure of the driver applied to rotate the platen.

7. In a typewriting machine, the combination with a roller platen, of a driver mounted co-axially therewith, and rotatable relatively to the platen, a coupling pin carried by and projectable from one side of said driver to lock the driver to the platen to cause the platen to be rotated forwardly with the driver, a cam on the opposite side of the driver for projecting said pin, and means to automatically retract said coupling pin and .permit the platen to be rotated in dependently, of the driver, said cam positioned to project said couplingpin and lock the driver to the platen when said driver is at an intermediate position during its moveand projecting from one side thereof to lock the driver to the platen to cause the platento be rotated forwardly with the driver, means to automatically retract said coupling pin and permit the platen to be rotated independently of the driver, a station- ,ary cam on the opposite side of the driver to project said coupling pin and lock the driver to the platen when said driver is movedin av direction to rotate the platen backwardly, said cam positioned to permit a limited rotation of the driverv independently of the platen, whereby the backward rotation of the platen by the driver is through a smaller angle than its forward rotation by the driver, and holding means to positively prevent 'the coupling pin from becoming disconnected 'from the platen during said backward rotation of the platen. Y Y

9. In a typewriting machine, the combina tion with a rotary platen, of a driver loosely mounted on the platen axle, a coupling pin carriedby the driver, means to project said pin in a direction lengthwise of the platen into locking engagement with the platen and thereby cause the'pl'aten to be rotated forwardly whenth'e driver is rotated, means to hold said coupling pin in its projected posi tion during the rotation. of the driver in a direction torotate the platen forwardly, a spring carried by the driver and operable to automatically retract the coupling pin and release the platen from the driver when the latter is at the limit of its rotation in said direction, and means to automatically pro-- ject said pin into locking relation with the platen when the driver is rotated in the opposite direction.

10. In a typewriting machine, the combination with a roller platen, of a driver therefor rotatable on the platen axle, a coupling pin carried by said driver, a holding plate to hold said pin, during a portion of the platen-advancing movement of the driver, projected into position to connectthe driver with the platen, said pin frictionally held in said position during the remainder of said movement, and a stop to limit said movement of the driver, said holding plate formed to permit the coupling pin to be retracted when the driver is at the limit of said movement, and thereby permit wheel loosely mounted on theplaten axle,

a "coupling pin extending transversely through said driving Wheel into position to lock the platen to the driving wheel, a stationary holding plate, along which said pin moves during the rotation of the driver to hold said pin in locking position, said holdingJ plate formed to permit the coupling pin to e retracted when the driver reaches a certain position, whereby the platen is released fromthe driver, and means to limit the rotation of the driver in both directions.

12. In a typewriting machine, the combination with a platen, of a line-space ratchet wheel connected to rotate therewith,

a driver mounted adjacent to said ratchet wheel, .a coupling pin mounted in said driver, an annular series of openings in said line-space wheel, said openingsbeing in the path of the coupling pin, whereby the latter 1 may be projected into any one of said opening s to connect the driver with the platen, a stationary plate on the side of the driver opposite the ratchet wheel to hold said coupling pin in engagement with the ratchet I 40 wheel and cause the platen to rotate the driver, and 'a stop to limit the rotation of the driver in rotating the platen forwardly, said holding plate formed to permit the coupling pinto be retracted as the driver nears said stop, whereby the platen may be rotated independently of the driver, and whereby said coupling pin, as the driver is rotated in the reverse direction, is engaged with the ratchet wheel to rotate the platen backwardly.

13. In a typewriting machine, the combination with a platen, of a line-space ratchet wheel connected to rotate therewith, a driver mounted adjacent to said ratchet Wheel, a coupling pin mounted in said driver, an annular series of openingsin said line-space wheel, said openings being in the path of the coupling pin, whereby the lat- "'ter may be projected into any one of said openings to connect the driver with the platen, a stationary plate on the side of the driver opposite the ratchet wheel to hold said coupling pin in engagement with the ratchet wheel and cause the platen to rotate with the driver, and means to release the coupling pin from the ratchet wheel when the driver reaches a predetermined position.

14. The combination with a roller platen, of as line-space ratchet wheel fixed to the platen'axle, a driver loose on the platen axle, a coupling pin. extending transversely through the driver, said ratchet wheel formedwith an annular series of openings in the path of said coupling pin, a stationary holdingplat'e to hold said coupling pin in one ofsaid openings to cause the platen to be rotated with the driver, and a stop tolimit the rotation of the driver in a direction to rotate the platen forwardly, said holding plate formed with a recess in position to permit the coupling pin to be withdrawn from the ratchet wheel at the end of said rotation of the driver and permit a limited rotation of the driver in the reverse direction independently of the platen, said recess having acam surface to project the coupling pin to reengage thedriver with the platen during the rotation ofthe driver in s -.id reverse direction.

15. The combination with a platen axle and a platen secured there-to, of linespacng mechanism comprising a. line-space rat(het wheel fixed to the platen axle, a platen d :iving disk mounted on the platen axle for ro-- tation relative to the platen, a stationary holding plate on the side of the driving disk opposite the line-spacing wheel, and a coupling pin extending transversely through the driving disk, said line-spacing wheel formed to have a locking engagement with the coupling pin,.said holding plate holding said pin locked to the line-space wheel during a portion of the rotation of the driving disk and formed to permit the release of said coupling pin from the line-space wheel when the driving disk reaches a predetermined position andto'again connect the coupling pin 1 to the line-space wheel when the driving disk is rotated in the reverse direction.

16. The combination with a platen and platen axle, of a linespace wheel secured to said axle, a driving disk loose on the axle, a stationary holding plate on the side of said disk opposite the line-space whee1, a coupling pin, extending through said diskand held by said plate in engagement with the line-space wheel to connect the driving disk to the platen, a spring to withdraw said coupling pin from the linespace wheel, and a stop to limit the rotation of the driving disk in a direction to rotate the platen forwardly, said holding plate formed to' permit said withdrawal of the locking pin when the driving disk is at the limit of its rotation in said direction.

17. In a typewriting machine, the combination with a platen, of a driver to rotate the platen, a coupler carried by the driver and movable into and out of position to couple the driver to the platen for rotating the platen, a stop to limit the forward rotation. of the platen, a ,stationary holding plate to engage said coupler and hold it in coupling position during a portion of the movement of the driver as the platen is rotated forwardly, said coupler frictionally held in coupling position during the final forward movement of the driver, and a spring to withdraw the coupler from coupling position when the driver reaches the limit of said movement, said holding plate operable to shift the coupler on the driver to coupling position when the driver reaches an intermediate point in its movement in the opposite direction. I

18. The c mbinationwith a platen, of a driver therefor, a coupler to connect the driver with the platen, and stationary holding means to hold the coupler in looking position during a portion of the rotation of the driver in one direction, said coupler being frictionally held in looking position during another portion of the rotation of the driverin said direction, said coupler being automatically released to permit the driver to rotate in the reverse direction independently of the platen during the range of its movement through which thecoupler was frictionally held in looking position, said holding means operable to re-connect the coupler to the platen and cause the platen to be driven "during the remaining portion of the-rotation of the driver in said reverse direction. 1

19. The combination with a rotary platen. of adriving disk normally disconnected from the platen to permit rotation of the platen independently thereof, said disk rotatable a limited distance in both directions, means to automatically connect the disk with the platen torotate the latter when the disk is rotated, and a stop carried by the disk and adj ustable thereon to different pesitions circumferentially of the disk, to adjustably limit the distance through which the disk is rotatable and thereby variably limit the distance through which the platen is rotatable by said disk.

20. The combination with a. rotary platen, of a driving disk normally disconnected from the platen to permit the latter to be rotated independently of the disk, stops carried by the disk to limit its rotation in both directions, and means to automatically connect the disk with the platen for rotating the platen a limited distance with the disk first in one direction and then a different distance in the otherdirection, one of said stops being adjustable along theperiphery of the disk to thereby vary the distance through which the platen is rotated by the disk.

21. :lhe combination with a rotary platen, of a driving disk normally disconnected from the platen to permit the latter to rotate independently of the disk, a coupler carried by said disk and movable thereon into and out of position for connecting the disk to rotate the platen, means for moving said coupler to coupling position when the disk is rotated in a direction to rotate the platen operating counter-stopto limit the movement of the disk in one direction, said lasta named stop being adjustable circumferential'ly on the disk to vary the distance through which the platen is rotated by the disk.

faces, said coupling pin movable into and out of position for engagement with a holding surface corresponding to the rotative position of the disk relative to the line-space wheel to thereby couple the disk to the platen, a stationary holding plate on the side of the disk opposite the line-space wheel for holding the said pin in coupling position as the disk is rotated, a stop to limit the rotation of the disk, andaspring to move the coupling pin to uncouple the.

disk, and thereby permit the platen and line-space wheelto rotate independently of the disk, said holding plate formed to per mit such uncoupling when the disk is at the limit of its rotation determined by said stop.

23. The combination with a rotary platen and a platen axle, of a line-space wheel fixed on said axle, a platen-driving disk loosely mounted on the axle, a coupling pin carried by said disk and extending transversely therethrough, the line-space wheel being provided with a series of holding surfaces, said coupling pin movable into and out of position for engagement with a holding surface corresponding to the rotative position of the disk relative to the line-space wheel to thereby couple the disk to the stationary holding plate on the si e of the disk opposite the line-space wheel for holding the said pin in coupling positionas the laten, a.

disk is rotated, stops on the disk to limit i from the line-space wheel when the disk is at the limit of its rotation in one direction, and a spring to withdraw the coupling pin when the disk is in such position, and there-- by permit the platen to be rotated independently of the disk, said recess being formed to permit the disk to be rotated from said stop position a limited distance independently of the platen, whereby the platen is rotated by the disk through a greater distance in one direction than in the other direction.

24. The combination with a rotary platen space wheel to thereby couple the disk to the platen, a stationary holding plate on the side of the disk opposite the line-space wheel for holding the said pin in coupling position as the disk is rotated,'stops on the disk to limit the rotation of the disk in both directions, said holding plate provided with a recess to permit the coupling pin to be withdrawn from the line-space wheel when the disk is at the limit of its rotation in one direction, a spring to withdraw the coupling pin when the disk is in such position, and thereby permit the platen to be rotated independently of the disk, said recess being formed to' permit the disk to be .rotated from said stop position a limited distance independently of the platen, whereby theplaten is rotated by the disk through a greater distance in one direction than in the other direction, one of said stops being adjustable circumferentially of the disk to variably limit the distance through which the platen is rotatable by the disk, and a graduated scale to indicate the position to a platen-driving disk which the stop is adjusted, and thereby indicate the distance through which the platen can be rotated by each operation of the disk.

and a platen axle journaled therein, of a rotary platen and line-space wheel secured to said axle, a driving disk loosely mounted on the axle adjacent the line-space wheel, a coupling pin carried by said disk and extending transversely therethrough, the linespace wheel provided with an annular series of openings in the path of said pin ,at angular distances corresponding to line-space rotations of the platen, a stationary holding disk loosely mounted on the platen axle on the side of the disk opposite the line-space wheel and operative to hold the coupling pin in engagement with any one of said openings for connecting the driving: disk with the platen to rotate the latter first in one direction and then in the other direction, stops to limit the rotation of the driving disk in both directions, said holding disk formed with a cam recess positioned to permit the coupling pin to be withdrawn from the line-space wheel when the driving disk is at the limit of its rotation in one direction, and a spring to withdraw the coupling pin when opposite said recess, said recess being formed to permit rotation of the driving disk in one direction through a limited range independently of the linespace wheel, said coupling pin being fric tionally held in coupling position by the pressure of the driving disk and line-space wheel thereagainst during the rotation of the driving disk in the reverse direction through said range of movement, whereby the platen is rotated by the driving disk through a greater angle in one direction than in the other'direction.

HERMANN V. FENGLER. Witnesses:

J. V. BLonoE'rT, WILLIAM A. HARTNETT.

25. The combination with a platen frame 

